The present invention relates to a method of producing separator materials for use in electrochemical processes, especially in lead storage batteries.
In electrochemical processes, especially in electrochemical energy storage processes, it is known to separate electrodes from one another by the use of separator materials. Such separator materials are chemically inert or neutral materials that are used in a porous or perforated state. For example, in the manufacture of lead storage batteries a thin sheet of polyethylene (PE foil) that is provided with silica embedments often is used as separator material.
It also is known that due to differing manufacturing processes, storage, and/or transport conditions affecting the energy storage device, ion migration or drift occurs, with the ions originating from electrodes and also diffusing, for example, into the separator material. Especially in the case of lead storage batteries, this causes a considerable deterioration of the deep discharge characteristic.
It is therefore an object of the present invention to provide a method of producing separator materials that minimizes deleterious effects of drift while also providing a reduction of the ion concentration in the separator material.